The invention concerns devices for applying therapeutic traction to the digits of the extremities(hands or feet) and more particularly to devices which are self-contained and which have more than one mode of use or application.
Traction systems and devices according to the invention may be applied to the digits of both hands and feet but for convenience the following discussion will be limited to the hand application.
Traction is indicated and potentially beneficial for a number of health conditions including arthritis and many devices are available. Application of a static tensile force to a digit requires, of course, a tension member which is fixed at both ends, one end connected to the digit and the other end anchored at a point fixed in relation to the point of attachment to the digit. Digital traction devices may be broadly classified into two groups according to the general location of the anchor or reaction point of the tension member. In the first group the anchor point is remote from the hand and its digits and may, with the help of an associated frame, be located on another part of the body such as the upper arm, or on the frame of a bed supporting the patient. In the second group, which may be classed broadly as self-contained, the anchor point is on the hand and/or wrist. These self-contained devices are potentially more compact and provide greater mobility for the patient.
The present invention is related to the self-contained group. Known devices in this class tend to be complex, requiring skilled application and custom fitting as well as being heavy and clumsy, offering serious hindrance to the patient's mobility and normal activities. Typically the ultimate anchoring point is the wrist or forearm so that the whole hand and the wrist itself is subject to whatever traction force is applied to the digit or digits, even though in some conditions whole hand traction is not indicated.